Pulley  xx



March 13, 1945. w. B. coLLn-:R

PULLEY Filed oct. 51, 1942- Patented Mar. 13, 1945 UNIT-12D STATES 1 PATE NT OFFICE William B. Collier, Tallmadge, Ohio, assignor to The B. F. Goodrich Company, New York, N. Y.,

a corporationof New York Application october 31, 1942, serial No. 464,055 comme.'A (C1. 74' 723o:. 5

`of the belt. Where belts are of uncovered rubber construction, or where belt dressings are employed such seating friction is exceptionally high and often results in the -belt lturning with respect to its direction of motion due to the fact that one side of the belt contacts with a side of the belt groove in advance of the other side and, as high friction prevents slippage, the belt rolls over.

It has also been found in the manufacture of belts containing exposed rubber composition, that it is difficult to feed such belts to forming or guiding pulley grooves because of resistance to seating and tendency to turn over because of adhesion to the pulley.

The present invention aims to overcome the foregoing and other difculties.

The principal objects of the invention are to `r reduce seating friction, to provide greater driving power, to prevent turning of belts in the groove, to reduce belt wear, and to provide an improved pulley construction.

'Ihese and other objects will appear from the following description and the accompanying drawing.

Of the drawing,

Fig. 1 is a side elevation of a pulley constructed according to and embodying the invention with a' portion of a belt, other portions of the belt being broken away.

Fig. 2 is a 'cross-section thereof taken on line 2-2 of Fig. 1`.

Fig. 3 is a detail perspective view showing a section of the pulley rim with the rollers in place, other parts being broken away.

In accordance with the invention, the pulley is formed with a belt receiving groove, the sides of which comprise surface elements movable toward and away from the axis of the pulley, preferably through rotation of the surface elements, so that a. minimum amount of seating friction is developed while movement of the elements circumferentially of the wheel is restricted.

Referringvto the drawing, the wheel IU has a hub II and a riml2,heldin relation thereto by a web I 3,;spokes,v or other means. Therim has-a cylindricalperipheral surface I4 for under-g lying a belt l5, which belt is of trapezoidal cross-A section and may be of the V-belt type or vthe hexagonal typefshown in broken lines at 15j. AI; each side of the surface .Mare a .circumferential series of retaining 4llear1-ssuch as ears` I 6, Il which project,laterally,.andrradially beyond the face I4 and are formedwith aperturesv I8, I9 to receivebeareina 1nsaneswlfl.` es pins 2 which' er1- ter circumferentially successive apertures with their axes tangential to a circle concentric with the wheel and span the spaces between the ears.

Rotatably mounted on the pins 20 between the adjacent ears, are anti-friction belt-engaging means, preferably in the form of cylindrical rollers 2|, 22 whose cylindrical faces extend beyond the ears and collectively dene the sides of a belt receiving groove. The apertures I8, I9 may initially be formed as slots to permit entrance of` the pins by movement laterally away from the center of the belt groove and the ears may then be deformed by peening or bending the material adjacent the apertures to clamp the pins in place or otherretaining means may be provided. The rollers are freely rotatable about the bearing pins and within the slots providedybetween the successive ears and the series of rollers at oppo.- site sides of the belt groove are spaced from each other so that whentheir rollers are tangent to the side faces `of the belt the cylindrical surface I 4 of the wheel will clear the bottom surface of the belt. With such an arrangement, the belt on progressively entering the groove will roll into place with very little-friction and will wedge rmly between the series of rollers and clear of the bottom of the groove, a condition conducive to transmission of power without slippage.

. When it is desired tov have the belt bottom on the cylindrical wheel surface I4, as where the pulley is used as a forming wheel in building V- belts, the rollers may be spaced farther apart accordingly.

While the rollers 2I, 22 have been shown with plain cylindrical surfaces, these surfaces may have curved faces for distributing the load and may be circumferentially Agrooved or knurled to provide greater resistance to slipping without substantially increasing loss of power due to friction of seating and unseating the belt. The margins of the rollers may be rounded, as shown, to prevent cutting of the belt. VWhile the circumferential grooves increase the holding` power circumferentially' of the pulley, they seat and unseat the used to support unvulcanized belt bodies having a 10 tacky surface, as entry of the belt into the grooves is facilitated without lateral turning due to the ro.- tation of the rollers whenJ contacted by the tacky" material.

Variations may be made withoutmiepartingjromr i551 the scope of the invention as it is defined by thee l following claims.

I claim:

l. A pulley having' rows of rotatablevfbelt=ene gagingV elements about its periphery presenting im tlieirrotatable "surfaces asr th'erfsdevslofr a -belterr gaging groove; saidelementsslieingq-circularfinsee; tion-1 and i being=restrained Itoi rotatin-a/'b'out axes extendingfgenera'llyin the cicumfrentialidirec;

2. A pully'fliaving: axially:spaoedapartxzseries of-cylindrical lroilersrabout'iitsperipheryf present? groove; said `elements'lo'eingfcircularvintsectionand beingrestrainedfto rotationiaboutfaxesextending angenerally' in* tlie circumferential? direction-s offtlie pulley.`A

3. A pulley having axially spaced-apart series of knurled cylindrical rollers about its periphery presenting their surfaces as the sides of a beltengaging groove, said rollers having their groovedening surfaces movable about axes extending generally in the circumferential direction of the pulley.

4;,lArpulleyrhaving axiallyfspaced-apart series of -ioylindricalrollers aboutitsiperiphery presenting their surfaces as the sides of a belt-engaging groove, said rollers having their groove-defining faces movable With relation to the pulley in a direction toward and from the axis of the pulley aaidlrollerseofl thezspaced-apart series being in aariallyfopposed frelation.

.Afpulleyrhaa/ing axially spaced-apart series of anti-,friction rollers about its periphery presenting their lsurfaces as the sides of a belt-engaenazgroove, said rollers being' circular in cross section and having their axes restrained to positions-tangent to '-circleseconcentric witl'itlieewlieel.

6'; A `pulley-1liaving-'a'peripheral 'channel ffr'itlie reception off' a= beltf of trapezoida'l! section;v said pulley having in the:sideawalls-offtlriacliannel beltrccmtactir'i-g rotatable1 elments= off circular cross section'ihavingperipheral surf aces rotatablymriov ableftbwardlandaway fromltlfieeaxisaof the'pully during seating and 'unseatingzofFthef-belt'l WnmmMiBa: commi. 

